This invention relates to a pressure regulating fuel delivery system suitable for a gas turbine engine, having a pressure regulator, together with an ultrasonic sensor and a densiometer to accurately measure the mass flow of fuel to the engine.
Conventional fuel delivery systems for gas turbine engines are expensive and include numerous complex parts. A typical fuel delivery system is controlled by scheduling fuel flow based upon a fuel metering valve position and a linear variable displacement transducer to provide feedback. The metering valve position is adjusted in closed loop to maintain the desired engine speed (and power setting). A low accuracy dual rotor turbine meter to measure totalized mass flow after the fuel metering unit. The totalized flow is used as a double check for the wing tank fuel level gauges. The dual rotor turbine meter is a volumetric device with limited accuracy, therefore it is not used for engine health monitoring.
The fuel metering valve, dual rotor turbine meter, linear variable displacement transducer, pressure regulator, and other components, are all quite complicated. The metering valve also creates a pressure drop within the system that generates extra heat in fuel and decreases the efficiency of the oil cooling system. Therefore, what is needed is a system that reduces heat load, eliminates the fuel metering valve, dual rotor turbine meter, and linear variable displacement transducer, and accurately measures the instantaneous and totalized mass flow to the burner, for engine health monitoring.